Physical and chemical characterization of guava (Psidium guajava L.) genotypes grown in subtropical condition

Guava is a high-value tropical fruit that is widely grown in tropical and subtropical regions around the world. In the adaptation studies carried out in Turkey, guava was determined as the most prominent species with its cold resistance feature. The use of seedlings in cultivation created a genetic variation and differences were observed between the resulting genotypes, especially in terms of fruit size, shape and colour. Based on this observation, this study aimed to characterize 13 different guava fruit genotypes based on physical, chemical, bioactive and aroma properties. In the adaptation studies carried out in Turkey, guava was determined as the most prominent species with its cold resistance feature. There is only one commercial variety namely ‘Ruby Supreme’ grown in Turkey. Presently, the interest of the guava cultivation has been increased and farmers were used seedling material instead of vegetative to establish orchard. Due to the cross pollination, it has been observed great variation in the population.  Therefore, it is important to select promising genotypes according to   fruit size, shape and colour.  The present study was evaluated 13 different guava genotypes according to physical, chemical, bioactive and aroma properties. Significant differences were observed among the genotypes. One genotype was found superior over all the genotypes, in terms of fruit weight (131.44 g) and length (82.00 mm). Although three genotypes were having lower values than the other samples in results of total soluble solids, they had higher results in terms of antioxidant capacity and total phenolic content. Two genotypes formed a separate group from all other genotypes in terms of (Z)-3-Hexen-1-yl acetate (sweet, pear, melon), 3-Hexenal (melon, tropical) and Ethyl alcohol (fruit and sweet) components. The flavor components are distinctive for the guava samples, as are the physical properties. It was also determined that the white guava genotypes had very different chemical and aromatic properties from other genotypes. The promising genotypes can be utilized in the future breeding programme to improve new guava varieties.